FILTER ELEMENT FOR A LIQUID FILTER

Abstract

An annular filter element, including: a filter medium having circumferentially closed about an axis and extended along the axis, the axis defining an axial direction; wherein the filter medium has a radially outer flow face and a radially inner flow face, the radially inner flow face surrounding an inner clean space in the filter element; wherein the filter element is through-flowable radially from a radial outside to a radial inside of the filter element; a water separation screen inserted into the clean space, the water separation screen formed separately from the filter element, the water separation screen connected to the filter element or to a component situated at the filter element.

Claims

1. An annular filter element, comprising: a filter medium having circumferentially closed about an axis and extended along the axis, the axis defining an axial direction; wherein the filter medium has a radially outer flow face and a radially inner flow face, the radially inner flow face surrounding an inner clean space in the filter element; wherein the filter element is through-flowable radially from a radial outside to a radial inside of the filter element; an end plate having: an axial inner surface; and an opposite axial outer surface; wherein the axial inner surface of the end disk is arranged on an axial end face of the filter medium; and a water separation screen inserted into the clean space, the water separation screen formed separately from the filter element, the water separation screen connected to the filter element or to a component situated at the filter element.

2. The filter element according to claim 1, wherein the filter element has an end plate arranged on an axial end face of the filter medium; wherein the water separation screen is connectable to the end plate.

3. The filter element according to claim 2, wherein the water separation screen has a collar arranged proximate to an axial end of the water separation screen; wherein a sealing element is provided between the collar and the end plate.

4. The filter element according to claim 3, wherein the sealing element is configured as a sealing lip integrally molded onto the collar.

5. The filter element according to claim 3, wherein the sealing element is configured as a separate sealing ring situated between the collar and the end plate.

6. The filter element according to claim 3, wherein the water separation screen has a separation shell having an outer diameter; wherein the collar has an outer diameter that is greater than the outer diameter of the separation shell.

7. The filter element according to claim 2, wherein the water separation screen is connected via a latch connection to the end plate.

8. The filter element according to claim 1, wherein the water separation screen is cylindrically formed.

9. The filter element according to claim 1, wherein the water separation screen is conically formed.

10. The filter element according to claim 1, wherein a coalescing element is arranged adjacent to the filter element.

11. The filter element according to claim 10, wherein the coalescing element is arranged at a clean side of the filter element.

12. The filter element according to claim 1, comprising: a tubular center pipe is inserted into the clean space of the filter element; the water separation screen is inserted into and arranged in the center pipe.

13. A liquid fuel filter, comprising: a filter housing; a filter element according to claim 1 arranged within an interior of the filter housing.

14. The liquid fuel filter according to claim 13, wherein the housing includes a water collecting space for collecting water separated from the fuel; wherein the clean space in the filter element is flow-connected at a first axial end to the water collecting space; wherein the clean space is flow-connected at an opposing second axial end to a liquid outflow line for the cleaned liquid.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Further advantages and expedient embodiments may be concluded from the further claims, the description of the figures and the drawings.

[0018] FIG. 1 shows a perspective view of a liquid filter for filtering fuel;

[0019] FIG. 2 shows a longitudinal section through the liquid filter having marked flow arrows to indicate the flow path;

[0020] FIG. 3 shows a perspective, partially sectional view of a filter element, which is part of the liquid filter, having a water separation screen situated in the interior clean space;

[0021] FIG. 4 shows a further, partially sectional illustration of the filter element;

[0022] FIG. 5 shows an enlarged view of detail V from FIG. 4;

[0023] FIG. 6 shows an end face connection between the water separation screen and an end plate of the filter element in a variation of the embodiment.

[0024] In the figures, same components are provided with the same reference characters.

DESCRIPTION OF THE INVENTION

[0025] FIG. 1 perspectively shows a fluid filter 1 for filtering fuel, preferably diesel fuel. In a filter housing 2, liquid filter 1 has a filter element for filtering the fuel. In the upper end face region of filter housing 2, a heating device 3 is located, in which the supplied fuel is preheated before it is fed into the filter element in filter housing 2. A radial inflow line 4 for supplying the unfiltered fuel and a radial outflow line 5 for discharging the filtered fuel is also located in the upper region of filter housing 2.

[0026] FIG. 2 shows liquid filter 1 in a longitudinal section. Filter housing 2 accommodates annular filter element 6, which is through-flown radially from the outside to the inside by the fluid to be filtered. Accordingly, the cylindrical interior in filter element 6 forms clean space 7 from which the cleaned fluid is axially discharged.

[0027] A center or support pipe 8, which preferably is made out of plastic and braces the filter medium of filter element 6 and which provides stability to said filter medium, is inserted into clean space 7 of filter element 6. Central pipe 8 lines clean space 7.

[0028] A coalescing element 9 delimited radially inwards by center pipe 8 is located on the radially interior side of the filter medium of filter element 6. An agglomeration of finely distributed droplets of water in the fuel occurs in coalescing element 9 so that said droplets accumulate into larger droplets.

[0029] A water collecting space 10, in which water separated when filtering the fluid is collected, is located in the bottom region near the ground in filter housing 2. The collected water can be discharged from water collecting space 10 in the filter housing via a bottom sided opening and a valve.

[0030] A water separation screen 11, embodied as a hollow cylinder and having an outer diameter which is smaller than the interior diameter of center pipe 8, is inserted into clean space 7 so that an intermediate annular space is formed. Water separation screen 11 extends axially like center pipe 8 over the total length of clean space 7 or of filter element 6. The droplets of water carried along in the fuel, are separated at the outer surface shell of water separation screen 11. As indicated by the vertical downward pointing arrow, the separated droplets of water are discharged via the bottom axial end face of clean space 7 into water collecting space 10.

[0031] The wall of water separation screen 11 has a plurality of passage openings, via which the cleaned fuel may through-flow radially inwards from the annular space between center pipe 8 and water separation screen 11 into the interior of water separation screen 11. Subsequently, the cleaned fuel liberated from the water droplets is axially discharged via the end face of clean space 7 lying axially on the top, which is flow-connected to outflow line 5.

[0032] FIG. 3 shows filter element 6 in a perspective and partially sectional view. Filter medium 12 of filter element 6 is embodied as a pleated filter and is enclosed on both end faces by respectively one end plate 13, 14. In the area of upper end plate 6, via the central opening of which the cleaned fluid is discharged from clean space 7, water separation screen 11 has a radially widened collar 15 connected in a latch-closing manner via snap or latch hooks 16 to end plate 13. Latch hooks 16 are molded at the inward facing side at end plate 13 or integrally formed with end plate 13 (see also FIGS. 4, 5). In the connected state, latch hooks 16 engage behind a circumferential, radially outer ring shoulder at collar 15.

[0033] As may particularly be concluded from FIG. 5, a sealing lip 17, which abuts at the radially inner side of latch hooks 16, is molded adjacent to the free end face and, in the radially outer area, to collar 15. Latch hooks 16 may optionally also be configured as a continuous circumferential latch ring at the bottom side of end plate 13. A flow-proof seal between the radially outer clean side having water containing fuel and the radially inner clean side having fuel not containing water is provided via sealing lip 17.

[0034] End plate 13 has on its axially outward facing end face an axially protruding support collar 20, onto which a cover 18 is fitted. On the radially inner side of support collar 20, a sealing ring 19 is located, which, as may be concluded from FIG. 3, is braced radially outwards at a section of end plate 13.

[0035] As may further be concluded from FIG. 5, the free end face of collar 15 is, in the assembled state, located directly below end plate 13. During assembly, water separation screen 11 has to be inserted axially from the opposite side into clean space 7 or center pipe 8.

[0036] FIG. 6 shows a variation of the embodiment of filter element 6, in which the sealing between water separation screen 11 and upper end plate 13, in contrast to the preceding exemplary embodiment, is not carried out via a molded sealing lip but via a separately configured sealing ring 21. Sealing ring 21 is braced radially inwards at a circumferential ring shoulder at end face support collar 20 of water separation screen 11. Sealing ring 21 abuts radially outwards at the inner surface of latch hooks 16 or, in the case of a circumferential embodiment, of the latch collar, which is integrally formed with end plate 13 and which is located at the bottom side of end plate 13. For installation, water separation screen 11 may be inserted in the axial direction from above through upper end plate 13 into the clean space in filter element 6.